Summary of Restricted Stock and Restricted Stock Unit Award Activity (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock unit awards that vested during the period	55,064
Fair value of restricted shares that vested during the period	$ 1,148	$ 8,029
Compensation expense recognized during the period	4,230	2,691
Income tax benefit (cost) related to restricted stock awards	$ (110)	$ 2,418
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock unit awards that vested during the period	14,744	112,070
Fair value of restricted shares that vested during the period	$ 303	$ 3,554
Accumulated dividends paid upon vesting of restricted stock unit awards	63	544
Compensation expense recognized during the period	438	1,420
Income tax benefit (cost) related to restricted stock awards	$ (129)	$ 821

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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